socket.c 54.8 KB
Newer Older
L
Linus Torvalds 已提交
1 2 3 4 5 6
/*
 * NET		An implementation of the SOCKET network access protocol.
 *
 * Version:	@(#)socket.c	1.1.93	18/02/95
 *
 * Authors:	Orest Zborowski, <obz@Kodak.COM>
7
 *		Ross Biro
L
Linus Torvalds 已提交
8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44
 *		Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
 *
 * Fixes:
 *		Anonymous	:	NOTSOCK/BADF cleanup. Error fix in
 *					shutdown()
 *		Alan Cox	:	verify_area() fixes
 *		Alan Cox	:	Removed DDI
 *		Jonathan Kamens	:	SOCK_DGRAM reconnect bug
 *		Alan Cox	:	Moved a load of checks to the very
 *					top level.
 *		Alan Cox	:	Move address structures to/from user
 *					mode above the protocol layers.
 *		Rob Janssen	:	Allow 0 length sends.
 *		Alan Cox	:	Asynchronous I/O support (cribbed from the
 *					tty drivers).
 *		Niibe Yutaka	:	Asynchronous I/O for writes (4.4BSD style)
 *		Jeff Uphoff	:	Made max number of sockets command-line
 *					configurable.
 *		Matti Aarnio	:	Made the number of sockets dynamic,
 *					to be allocated when needed, and mr.
 *					Uphoff's max is used as max to be
 *					allowed to allocate.
 *		Linus		:	Argh. removed all the socket allocation
 *					altogether: it's in the inode now.
 *		Alan Cox	:	Made sock_alloc()/sock_release() public
 *					for NetROM and future kernel nfsd type
 *					stuff.
 *		Alan Cox	:	sendmsg/recvmsg basics.
 *		Tom Dyas	:	Export net symbols.
 *		Marcin Dalecki	:	Fixed problems with CONFIG_NET="n".
 *		Alan Cox	:	Added thread locking to sys_* calls
 *					for sockets. May have errors at the
 *					moment.
 *		Kevin Buhr	:	Fixed the dumb errors in the above.
 *		Andi Kleen	:	Some small cleanups, optimizations,
 *					and fixed a copy_from_user() bug.
 *		Tigran Aivazian	:	sys_send(args) calls sys_sendto(args, NULL, 0)
45
 *		Tigran Aivazian	:	Made listen(2) backlog sanity checks
L
Linus Torvalds 已提交
46 47 48 49 50 51 52 53 54 55
 *					protocol-independent
 *
 *
 *		This program is free software; you can redistribute it and/or
 *		modify it under the terms of the GNU General Public License
 *		as published by the Free Software Foundation; either version
 *		2 of the License, or (at your option) any later version.
 *
 *
 *	This module is effectively the top level interface to the BSD socket
56
 *	paradigm.
L
Linus Torvalds 已提交
57 58 59 60 61 62 63 64 65
 *
 *	Based upon Swansea University Computer Society NET3.039
 */

#include <linux/mm.h>
#include <linux/socket.h>
#include <linux/file.h>
#include <linux/net.h>
#include <linux/interrupt.h>
66
#include <linux/rcupdate.h>
L
Linus Torvalds 已提交
67 68 69
#include <linux/netdevice.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
A
Arjan van de Ven 已提交
70
#include <linux/mutex.h>
L
Linus Torvalds 已提交
71 72
#include <linux/wanrouter.h>
#include <linux/if_bridge.h>
73 74
#include <linux/if_frad.h>
#include <linux/if_vlan.h>
L
Linus Torvalds 已提交
75 76 77 78 79 80 81 82 83 84
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/cache.h>
#include <linux/module.h>
#include <linux/highmem.h>
#include <linux/mount.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/compat.h>
#include <linux/kmod.h>
85
#include <linux/audit.h>
86
#include <linux/wireless.h>
87
#include <linux/nsproxy.h>
L
Linus Torvalds 已提交
88 89 90 91 92 93 94 95 96 97

#include <asm/uaccess.h>
#include <asm/unistd.h>

#include <net/compat.h>

#include <net/sock.h>
#include <linux/netfilter.h>

static int sock_no_open(struct inode *irrelevant, struct file *dontcare);
98 99 100 101
static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov,
			 unsigned long nr_segs, loff_t pos);
static ssize_t sock_aio_write(struct kiocb *iocb, const struct iovec *iov,
			  unsigned long nr_segs, loff_t pos);
102
static int sock_mmap(struct file *file, struct vm_area_struct *vma);
L
Linus Torvalds 已提交
103 104 105 106

static int sock_close(struct inode *inode, struct file *file);
static unsigned int sock_poll(struct file *file,
			      struct poll_table_struct *wait);
107
static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
108 109
#ifdef CONFIG_COMPAT
static long compat_sock_ioctl(struct file *file,
110
			      unsigned int cmd, unsigned long arg);
111
#endif
L
Linus Torvalds 已提交
112 113 114 115 116 117 118 119 120
static int sock_fasync(int fd, struct file *filp, int on);
static ssize_t sock_sendpage(struct file *file, struct page *page,
			     int offset, size_t size, loff_t *ppos, int more);

/*
 *	Socket files have a set of 'special' operations as well as the generic file ones. These don't appear
 *	in the operation structures but are done directly via the socketcall() multiplexor.
 */

121
static const struct file_operations socket_file_ops = {
L
Linus Torvalds 已提交
122 123 124 125 126 127
	.owner =	THIS_MODULE,
	.llseek =	no_llseek,
	.aio_read =	sock_aio_read,
	.aio_write =	sock_aio_write,
	.poll =		sock_poll,
	.unlocked_ioctl = sock_ioctl,
128 129 130
#ifdef CONFIG_COMPAT
	.compat_ioctl = compat_sock_ioctl,
#endif
L
Linus Torvalds 已提交
131 132 133 134
	.mmap =		sock_mmap,
	.open =		sock_no_open,	/* special open code to disallow open via /proc */
	.release =	sock_close,
	.fasync =	sock_fasync,
135 136
	.sendpage =	sock_sendpage,
	.splice_write = generic_splice_sendpage,
L
Linus Torvalds 已提交
137 138 139 140 141 142 143
};

/*
 *	The protocol list. Each protocol is registered in here.
 */

static DEFINE_SPINLOCK(net_family_lock);
144
static const struct net_proto_family *net_families[NPROTO] __read_mostly;
L
Linus Torvalds 已提交
145 146 147 148 149 150 151 152

/*
 *	Statistics counters of the socket lists
 */

static DEFINE_PER_CPU(int, sockets_in_use) = 0;

/*
153 154 155
 * Support routines.
 * Move socket addresses back and forth across the kernel/user
 * divide and look after the messy bits.
L
Linus Torvalds 已提交
156 157
 */

158
#define MAX_SOCK_ADDR	128		/* 108 for Unix domain -
L
Linus Torvalds 已提交
159 160
					   16 for IP, 16 for IPX,
					   24 for IPv6,
161
					   about 80 for AX.25
L
Linus Torvalds 已提交
162 163
					   must be at least one bigger than
					   the AF_UNIX size (see net/unix/af_unix.c
164
					   :unix_mkname()).
L
Linus Torvalds 已提交
165
					 */
166

L
Linus Torvalds 已提交
167 168 169 170 171 172 173 174 175 176 177 178 179
/**
 *	move_addr_to_kernel	-	copy a socket address into kernel space
 *	@uaddr: Address in user space
 *	@kaddr: Address in kernel space
 *	@ulen: Length in user space
 *
 *	The address is copied into kernel space. If the provided address is
 *	too long an error code of -EINVAL is returned. If the copy gives
 *	invalid addresses -EFAULT is returned. On a success 0 is returned.
 */

int move_addr_to_kernel(void __user *uaddr, int ulen, void *kaddr)
{
180
	if (ulen < 0 || ulen > MAX_SOCK_ADDR)
L
Linus Torvalds 已提交
181
		return -EINVAL;
182
	if (ulen == 0)
L
Linus Torvalds 已提交
183
		return 0;
184
	if (copy_from_user(kaddr, uaddr, ulen))
L
Linus Torvalds 已提交
185
		return -EFAULT;
186
	return audit_sockaddr(ulen, kaddr);
L
Linus Torvalds 已提交
187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204
}

/**
 *	move_addr_to_user	-	copy an address to user space
 *	@kaddr: kernel space address
 *	@klen: length of address in kernel
 *	@uaddr: user space address
 *	@ulen: pointer to user length field
 *
 *	The value pointed to by ulen on entry is the buffer length available.
 *	This is overwritten with the buffer space used. -EINVAL is returned
 *	if an overlong buffer is specified or a negative buffer size. -EFAULT
 *	is returned if either the buffer or the length field are not
 *	accessible.
 *	After copying the data up to the limit the user specifies, the true
 *	length of the data is written over the length limit the user
 *	specified. Zero is returned for a success.
 */
205 206 207

int move_addr_to_user(void *kaddr, int klen, void __user *uaddr,
		      int __user *ulen)
L
Linus Torvalds 已提交
208 209 210 211
{
	int err;
	int len;

212 213
	err = get_user(len, ulen);
	if (err)
L
Linus Torvalds 已提交
214
		return err;
215 216 217
	if (len > klen)
		len = klen;
	if (len < 0 || len > MAX_SOCK_ADDR)
L
Linus Torvalds 已提交
218
		return -EINVAL;
219
	if (len) {
S
Steve Grubb 已提交
220 221
		if (audit_sockaddr(klen, kaddr))
			return -ENOMEM;
222
		if (copy_to_user(uaddr, kaddr, len))
L
Linus Torvalds 已提交
223 224 225
			return -EFAULT;
	}
	/*
226 227
	 *      "fromlen shall refer to the value before truncation.."
	 *                      1003.1g
L
Linus Torvalds 已提交
228 229 230 231 232 233
	 */
	return __put_user(klen, ulen);
}

#define SOCKFS_MAGIC 0x534F434B

234
static struct kmem_cache *sock_inode_cachep __read_mostly;
L
Linus Torvalds 已提交
235 236 237 238

static struct inode *sock_alloc_inode(struct super_block *sb)
{
	struct socket_alloc *ei;
239

240
	ei = kmem_cache_alloc(sock_inode_cachep, GFP_KERNEL);
L
Linus Torvalds 已提交
241 242 243
	if (!ei)
		return NULL;
	init_waitqueue_head(&ei->socket.wait);
244

L
Linus Torvalds 已提交
245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260
	ei->socket.fasync_list = NULL;
	ei->socket.state = SS_UNCONNECTED;
	ei->socket.flags = 0;
	ei->socket.ops = NULL;
	ei->socket.sk = NULL;
	ei->socket.file = NULL;

	return &ei->vfs_inode;
}

static void sock_destroy_inode(struct inode *inode)
{
	kmem_cache_free(sock_inode_cachep,
			container_of(inode, struct socket_alloc, vfs_inode));
}

261
static void init_once(struct kmem_cache *cachep, void *foo)
L
Linus Torvalds 已提交
262
{
263
	struct socket_alloc *ei = (struct socket_alloc *)foo;
L
Linus Torvalds 已提交
264

C
Christoph Lameter 已提交
265
	inode_init_once(&ei->vfs_inode);
L
Linus Torvalds 已提交
266
}
267

L
Linus Torvalds 已提交
268 269 270
static int init_inodecache(void)
{
	sock_inode_cachep = kmem_cache_create("sock_inode_cache",
271 272 273 274 275
					      sizeof(struct socket_alloc),
					      0,
					      (SLAB_HWCACHE_ALIGN |
					       SLAB_RECLAIM_ACCOUNT |
					       SLAB_MEM_SPREAD),
276
					      init_once);
L
Linus Torvalds 已提交
277 278 279 280 281 282 283 284 285 286 287
	if (sock_inode_cachep == NULL)
		return -ENOMEM;
	return 0;
}

static struct super_operations sockfs_ops = {
	.alloc_inode =	sock_alloc_inode,
	.destroy_inode =sock_destroy_inode,
	.statfs =	simple_statfs,
};

288
static int sockfs_get_sb(struct file_system_type *fs_type,
289 290
			 int flags, const char *dev_name, void *data,
			 struct vfsmount *mnt)
L
Linus Torvalds 已提交
291
{
292 293
	return get_sb_pseudo(fs_type, "socket:", &sockfs_ops, SOCKFS_MAGIC,
			     mnt);
L
Linus Torvalds 已提交
294 295
}

296
static struct vfsmount *sock_mnt __read_mostly;
L
Linus Torvalds 已提交
297 298 299 300 301 302

static struct file_system_type sock_fs_type = {
	.name =		"sockfs",
	.get_sb =	sockfs_get_sb,
	.kill_sb =	kill_anon_super,
};
303

L
Linus Torvalds 已提交
304 305
static int sockfs_delete_dentry(struct dentry *dentry)
{
306 307 308 309 310 311 312 313
	/*
	 * At creation time, we pretended this dentry was hashed
	 * (by clearing DCACHE_UNHASHED bit in d_flags)
	 * At delete time, we restore the truth : not hashed.
	 * (so that dput() can proceed correctly)
	 */
	dentry->d_flags |= DCACHE_UNHASHED;
	return 0;
L
Linus Torvalds 已提交
314
}
315 316 317 318 319 320 321 322 323 324

/*
 * sockfs_dname() is called from d_path().
 */
static char *sockfs_dname(struct dentry *dentry, char *buffer, int buflen)
{
	return dynamic_dname(dentry, buffer, buflen, "socket:[%lu]",
				dentry->d_inode->i_ino);
}

L
Linus Torvalds 已提交
325
static struct dentry_operations sockfs_dentry_operations = {
326
	.d_delete = sockfs_delete_dentry,
327
	.d_dname  = sockfs_dname,
L
Linus Torvalds 已提交
328 329 330 331 332
};

/*
 *	Obtains the first available file descriptor and sets it up for use.
 *
333 334
 *	These functions create file structures and maps them to fd space
 *	of the current process. On success it returns file descriptor
L
Linus Torvalds 已提交
335 336 337 338 339 340 341 342 343 344 345 346
 *	and file struct implicitly stored in sock->file.
 *	Note that another thread may close file descriptor before we return
 *	from this function. We use the fact that now we do not refer
 *	to socket after mapping. If one day we will need it, this
 *	function will increment ref. count on file by 1.
 *
 *	In any case returned fd MAY BE not valid!
 *	This race condition is unavoidable
 *	with shared fd spaces, we cannot solve it inside kernel,
 *	but we take care of internal coherence yet.
 */

347
static int sock_alloc_fd(struct file **filep)
L
Linus Torvalds 已提交
348 349 350 351
{
	int fd;

	fd = get_unused_fd();
352
	if (likely(fd >= 0)) {
L
Linus Torvalds 已提交
353 354
		struct file *file = get_empty_filp();

355 356
		*filep = file;
		if (unlikely(!file)) {
L
Linus Torvalds 已提交
357
			put_unused_fd(fd);
358
			return -ENFILE;
L
Linus Torvalds 已提交
359
		}
360 361 362 363
	} else
		*filep = NULL;
	return fd;
}
L
Linus Torvalds 已提交
364

365 366
static int sock_attach_fd(struct socket *sock, struct file *file)
{
367
	struct dentry *dentry;
368
	struct qstr name = { .name = "" };
369

370 371
	dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name);
	if (unlikely(!dentry))
372 373
		return -ENOMEM;

374
	dentry->d_op = &sockfs_dentry_operations;
375 376 377 378 379
	/*
	 * We dont want to push this dentry into global dentry hash table.
	 * We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED
	 * This permits a working /proc/$pid/fd/XXX on sockets
	 */
380 381
	dentry->d_flags &= ~DCACHE_UNHASHED;
	d_instantiate(dentry, SOCK_INODE(sock));
382 383

	sock->file = file;
384 385 386
	init_file(file, sock_mnt, dentry, FMODE_READ | FMODE_WRITE,
		  &socket_file_ops);
	SOCK_INODE(sock)->i_fop = &socket_file_ops;
387 388 389
	file->f_flags = O_RDWR;
	file->f_pos = 0;
	file->private_data = sock;
L
Linus Torvalds 已提交
390

391 392 393 394 395 396 397 398 399 400 401 402 403
	return 0;
}

int sock_map_fd(struct socket *sock)
{
	struct file *newfile;
	int fd = sock_alloc_fd(&newfile);

	if (likely(fd >= 0)) {
		int err = sock_attach_fd(sock, newfile);

		if (unlikely(err < 0)) {
			put_filp(newfile);
L
Linus Torvalds 已提交
404
			put_unused_fd(fd);
405
			return err;
L
Linus Torvalds 已提交
406
		}
407
		fd_install(fd, newfile);
L
Linus Torvalds 已提交
408 409 410 411
	}
	return fd;
}

412 413 414 415 416
static struct socket *sock_from_file(struct file *file, int *err)
{
	if (file->f_op == &socket_file_ops)
		return file->private_data;	/* set in sock_map_fd */

E
Eric Dumazet 已提交
417 418
	*err = -ENOTSOCK;
	return NULL;
419 420
}

L
Linus Torvalds 已提交
421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438
/**
 *	sockfd_lookup	- 	Go from a file number to its socket slot
 *	@fd: file handle
 *	@err: pointer to an error code return
 *
 *	The file handle passed in is locked and the socket it is bound
 *	too is returned. If an error occurs the err pointer is overwritten
 *	with a negative errno code and NULL is returned. The function checks
 *	for both invalid handles and passing a handle which is not a socket.
 *
 *	On a success the socket object pointer is returned.
 */

struct socket *sockfd_lookup(int fd, int *err)
{
	struct file *file;
	struct socket *sock;

439 440
	file = fget(fd);
	if (!file) {
L
Linus Torvalds 已提交
441 442 443
		*err = -EBADF;
		return NULL;
	}
444

445 446
	sock = sock_from_file(file, err);
	if (!sock)
L
Linus Torvalds 已提交
447
		fput(file);
448 449
	return sock;
}
L
Linus Torvalds 已提交
450

451 452 453 454 455
static struct socket *sockfd_lookup_light(int fd, int *err, int *fput_needed)
{
	struct file *file;
	struct socket *sock;

456
	*err = -EBADF;
457 458 459 460 461 462
	file = fget_light(fd, fput_needed);
	if (file) {
		sock = sock_from_file(file, err);
		if (sock)
			return sock;
		fput_light(file, *fput_needed);
L
Linus Torvalds 已提交
463
	}
464
	return NULL;
L
Linus Torvalds 已提交
465 466 467 468
}

/**
 *	sock_alloc	-	allocate a socket
469
 *
L
Linus Torvalds 已提交
470 471 472 473 474 475 476
 *	Allocate a new inode and socket object. The two are bound together
 *	and initialised. The socket is then returned. If we are out of inodes
 *	NULL is returned.
 */

static struct socket *sock_alloc(void)
{
477 478
	struct inode *inode;
	struct socket *sock;
L
Linus Torvalds 已提交
479 480 481 482 483 484 485

	inode = new_inode(sock_mnt->mnt_sb);
	if (!inode)
		return NULL;

	sock = SOCKET_I(inode);

486
	inode->i_mode = S_IFSOCK | S_IRWXUGO;
L
Linus Torvalds 已提交
487 488 489 490 491 492 493 494 495 496 497 498 499
	inode->i_uid = current->fsuid;
	inode->i_gid = current->fsgid;

	get_cpu_var(sockets_in_use)++;
	put_cpu_var(sockets_in_use);
	return sock;
}

/*
 *	In theory you can't get an open on this inode, but /proc provides
 *	a back door. Remember to keep it shut otherwise you'll let the
 *	creepy crawlies in.
 */
500

L
Linus Torvalds 已提交
501 502 503 504 505
static int sock_no_open(struct inode *irrelevant, struct file *dontcare)
{
	return -ENXIO;
}

506
const struct file_operations bad_sock_fops = {
L
Linus Torvalds 已提交
507 508 509 510 511 512 513 514 515 516
	.owner = THIS_MODULE,
	.open = sock_no_open,
};

/**
 *	sock_release	-	close a socket
 *	@sock: socket to close
 *
 *	The socket is released from the protocol stack if it has a release
 *	callback, and the inode is then released if the socket is bound to
517
 *	an inode not a file.
L
Linus Torvalds 已提交
518
 */
519

L
Linus Torvalds 已提交
520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538
void sock_release(struct socket *sock)
{
	if (sock->ops) {
		struct module *owner = sock->ops->owner;

		sock->ops->release(sock);
		sock->ops = NULL;
		module_put(owner);
	}

	if (sock->fasync_list)
		printk(KERN_ERR "sock_release: fasync list not empty!\n");

	get_cpu_var(sockets_in_use)--;
	put_cpu_var(sockets_in_use);
	if (!sock->file) {
		iput(SOCK_INODE(sock));
		return;
	}
539
	sock->file = NULL;
L
Linus Torvalds 已提交
540 541
}

542
static inline int __sock_sendmsg(struct kiocb *iocb, struct socket *sock,
L
Linus Torvalds 已提交
543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584
				 struct msghdr *msg, size_t size)
{
	struct sock_iocb *si = kiocb_to_siocb(iocb);
	int err;

	si->sock = sock;
	si->scm = NULL;
	si->msg = msg;
	si->size = size;

	err = security_socket_sendmsg(sock, msg, size);
	if (err)
		return err;

	return sock->ops->sendmsg(iocb, sock, msg, size);
}

int sock_sendmsg(struct socket *sock, struct msghdr *msg, size_t size)
{
	struct kiocb iocb;
	struct sock_iocb siocb;
	int ret;

	init_sync_kiocb(&iocb, NULL);
	iocb.private = &siocb;
	ret = __sock_sendmsg(&iocb, sock, msg, size);
	if (-EIOCBQUEUED == ret)
		ret = wait_on_sync_kiocb(&iocb);
	return ret;
}

int kernel_sendmsg(struct socket *sock, struct msghdr *msg,
		   struct kvec *vec, size_t num, size_t size)
{
	mm_segment_t oldfs = get_fs();
	int result;

	set_fs(KERNEL_DS);
	/*
	 * the following is safe, since for compiler definitions of kvec and
	 * iovec are identical, yielding the same in-core layout and alignment
	 */
585
	msg->msg_iov = (struct iovec *)vec;
L
Linus Torvalds 已提交
586 587 588 589 590 591
	msg->msg_iovlen = num;
	result = sock_sendmsg(sock, msg, size);
	set_fs(oldfs);
	return result;
}

592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620
/*
 * called from sock_recv_timestamp() if sock_flag(sk, SOCK_RCVTSTAMP)
 */
void __sock_recv_timestamp(struct msghdr *msg, struct sock *sk,
	struct sk_buff *skb)
{
	ktime_t kt = skb->tstamp;

	if (!sock_flag(sk, SOCK_RCVTSTAMPNS)) {
		struct timeval tv;
		/* Race occurred between timestamp enabling and packet
		   receiving.  Fill in the current time for now. */
		if (kt.tv64 == 0)
			kt = ktime_get_real();
		skb->tstamp = kt;
		tv = ktime_to_timeval(kt);
		put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMP, sizeof(tv), &tv);
	} else {
		struct timespec ts;
		/* Race occurred between timestamp enabling and packet
		   receiving.  Fill in the current time for now. */
		if (kt.tv64 == 0)
			kt = ktime_get_real();
		skb->tstamp = kt;
		ts = ktime_to_timespec(kt);
		put_cmsg(msg, SOL_SOCKET, SCM_TIMESTAMPNS, sizeof(ts), &ts);
	}
}

621 622
EXPORT_SYMBOL_GPL(__sock_recv_timestamp);

623
static inline int __sock_recvmsg(struct kiocb *iocb, struct socket *sock,
L
Linus Torvalds 已提交
624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641
				 struct msghdr *msg, size_t size, int flags)
{
	int err;
	struct sock_iocb *si = kiocb_to_siocb(iocb);

	si->sock = sock;
	si->scm = NULL;
	si->msg = msg;
	si->size = size;
	si->flags = flags;

	err = security_socket_recvmsg(sock, msg, size, flags);
	if (err)
		return err;

	return sock->ops->recvmsg(iocb, sock, msg, size, flags);
}

642
int sock_recvmsg(struct socket *sock, struct msghdr *msg,
L
Linus Torvalds 已提交
643 644 645 646 647 648
		 size_t size, int flags)
{
	struct kiocb iocb;
	struct sock_iocb siocb;
	int ret;

649
	init_sync_kiocb(&iocb, NULL);
L
Linus Torvalds 已提交
650 651 652 653 654 655 656
	iocb.private = &siocb;
	ret = __sock_recvmsg(&iocb, sock, msg, size, flags);
	if (-EIOCBQUEUED == ret)
		ret = wait_on_sync_kiocb(&iocb);
	return ret;
}

657 658
int kernel_recvmsg(struct socket *sock, struct msghdr *msg,
		   struct kvec *vec, size_t num, size_t size, int flags)
L
Linus Torvalds 已提交
659 660 661 662 663 664 665 666 667
{
	mm_segment_t oldfs = get_fs();
	int result;

	set_fs(KERNEL_DS);
	/*
	 * the following is safe, since for compiler definitions of kvec and
	 * iovec are identical, yielding the same in-core layout and alignment
	 */
668
	msg->msg_iov = (struct iovec *)vec, msg->msg_iovlen = num;
L
Linus Torvalds 已提交
669 670 671 672 673 674 675 676 677 678
	result = sock_recvmsg(sock, msg, size, flags);
	set_fs(oldfs);
	return result;
}

static void sock_aio_dtor(struct kiocb *iocb)
{
	kfree(iocb->private);
}

679 680
static ssize_t sock_sendpage(struct file *file, struct page *page,
			     int offset, size_t size, loff_t *ppos, int more)
L
Linus Torvalds 已提交
681 682 683 684
{
	struct socket *sock;
	int flags;

685 686 687 688 689 690 691 692
	sock = file->private_data;

	flags = !(file->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;
	if (more)
		flags |= MSG_MORE;

	return sock->ops->sendpage(sock, page, offset, size, flags);
}
L
Linus Torvalds 已提交
693

694
static struct sock_iocb *alloc_sock_iocb(struct kiocb *iocb,
695
					 struct sock_iocb *siocb)
696 697 698 699 700
{
	if (!is_sync_kiocb(iocb)) {
		siocb = kmalloc(sizeof(*siocb), GFP_KERNEL);
		if (!siocb)
			return NULL;
L
Linus Torvalds 已提交
701 702 703
		iocb->ki_dtor = sock_aio_dtor;
	}

704 705 706
	siocb->kiocb = iocb;
	iocb->private = siocb;
	return siocb;
L
Linus Torvalds 已提交
707 708
}

709
static ssize_t do_sock_read(struct msghdr *msg, struct kiocb *iocb,
710 711
		struct file *file, const struct iovec *iov,
		unsigned long nr_segs)
712 713 714 715
{
	struct socket *sock = file->private_data;
	size_t size = 0;
	int i;
L
Linus Torvalds 已提交
716

717 718
	for (i = 0; i < nr_segs; i++)
		size += iov[i].iov_len;
L
Linus Torvalds 已提交
719

720 721 722 723
	msg->msg_name = NULL;
	msg->msg_namelen = 0;
	msg->msg_control = NULL;
	msg->msg_controllen = 0;
724
	msg->msg_iov = (struct iovec *)iov;
725 726 727 728 729 730
	msg->msg_iovlen = nr_segs;
	msg->msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;

	return __sock_recvmsg(iocb, sock, msg, size, msg->msg_flags);
}

731 732
static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov,
				unsigned long nr_segs, loff_t pos)
733 734 735
{
	struct sock_iocb siocb, *x;

L
Linus Torvalds 已提交
736 737
	if (pos != 0)
		return -ESPIPE;
738 739

	if (iocb->ki_left == 0)	/* Match SYS5 behaviour */
L
Linus Torvalds 已提交
740 741
		return 0;

742 743

	x = alloc_sock_iocb(iocb, &siocb);
744 745
	if (!x)
		return -ENOMEM;
746
	return do_sock_read(&x->async_msg, iocb, iocb->ki_filp, iov, nr_segs);
L
Linus Torvalds 已提交
747 748
}

749
static ssize_t do_sock_write(struct msghdr *msg, struct kiocb *iocb,
750 751
			struct file *file, const struct iovec *iov,
			unsigned long nr_segs)
L
Linus Torvalds 已提交
752
{
753 754 755
	struct socket *sock = file->private_data;
	size_t size = 0;
	int i;
L
Linus Torvalds 已提交
756

757 758
	for (i = 0; i < nr_segs; i++)
		size += iov[i].iov_len;
L
Linus Torvalds 已提交
759

760 761 762 763
	msg->msg_name = NULL;
	msg->msg_namelen = 0;
	msg->msg_control = NULL;
	msg->msg_controllen = 0;
764
	msg->msg_iov = (struct iovec *)iov;
765 766 767 768
	msg->msg_iovlen = nr_segs;
	msg->msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;
	if (sock->type == SOCK_SEQPACKET)
		msg->msg_flags |= MSG_EOR;
L
Linus Torvalds 已提交
769

770
	return __sock_sendmsg(iocb, sock, msg, size);
L
Linus Torvalds 已提交
771 772
}

773 774
static ssize_t sock_aio_write(struct kiocb *iocb, const struct iovec *iov,
			  unsigned long nr_segs, loff_t pos)
775 776
{
	struct sock_iocb siocb, *x;
L
Linus Torvalds 已提交
777

778 779
	if (pos != 0)
		return -ESPIPE;
780 781

	x = alloc_sock_iocb(iocb, &siocb);
782 783
	if (!x)
		return -ENOMEM;
L
Linus Torvalds 已提交
784

785
	return do_sock_write(&x->async_msg, iocb, iocb->ki_filp, iov, nr_segs);
L
Linus Torvalds 已提交
786 787 788 789 790 791 792
}

/*
 * Atomic setting of ioctl hooks to avoid race
 * with module unload.
 */

A
Arjan van de Ven 已提交
793
static DEFINE_MUTEX(br_ioctl_mutex);
794
static int (*br_ioctl_hook) (struct net *, unsigned int cmd, void __user *arg) = NULL;
L
Linus Torvalds 已提交
795

796
void brioctl_set(int (*hook) (struct net *, unsigned int, void __user *))
L
Linus Torvalds 已提交
797
{
A
Arjan van de Ven 已提交
798
	mutex_lock(&br_ioctl_mutex);
L
Linus Torvalds 已提交
799
	br_ioctl_hook = hook;
A
Arjan van de Ven 已提交
800
	mutex_unlock(&br_ioctl_mutex);
L
Linus Torvalds 已提交
801
}
802

L
Linus Torvalds 已提交
803 804
EXPORT_SYMBOL(brioctl_set);

A
Arjan van de Ven 已提交
805
static DEFINE_MUTEX(vlan_ioctl_mutex);
806
static int (*vlan_ioctl_hook) (struct net *, void __user *arg);
L
Linus Torvalds 已提交
807

808
void vlan_ioctl_set(int (*hook) (struct net *, void __user *))
L
Linus Torvalds 已提交
809
{
A
Arjan van de Ven 已提交
810
	mutex_lock(&vlan_ioctl_mutex);
L
Linus Torvalds 已提交
811
	vlan_ioctl_hook = hook;
A
Arjan van de Ven 已提交
812
	mutex_unlock(&vlan_ioctl_mutex);
L
Linus Torvalds 已提交
813
}
814

L
Linus Torvalds 已提交
815 816
EXPORT_SYMBOL(vlan_ioctl_set);

A
Arjan van de Ven 已提交
817
static DEFINE_MUTEX(dlci_ioctl_mutex);
818
static int (*dlci_ioctl_hook) (unsigned int, void __user *);
L
Linus Torvalds 已提交
819

820
void dlci_ioctl_set(int (*hook) (unsigned int, void __user *))
L
Linus Torvalds 已提交
821
{
A
Arjan van de Ven 已提交
822
	mutex_lock(&dlci_ioctl_mutex);
L
Linus Torvalds 已提交
823
	dlci_ioctl_hook = hook;
A
Arjan van de Ven 已提交
824
	mutex_unlock(&dlci_ioctl_mutex);
L
Linus Torvalds 已提交
825
}
826

L
Linus Torvalds 已提交
827 828 829 830 831 832 833 834 835 836
EXPORT_SYMBOL(dlci_ioctl_set);

/*
 *	With an ioctl, arg may well be a user mode pointer, but we don't know
 *	what to do with it - that's up to the protocol still.
 */

static long sock_ioctl(struct file *file, unsigned cmd, unsigned long arg)
{
	struct socket *sock;
837
	struct sock *sk;
L
Linus Torvalds 已提交
838 839
	void __user *argp = (void __user *)arg;
	int pid, err;
840
	struct net *net;
L
Linus Torvalds 已提交
841

842
	sock = file->private_data;
843 844
	sk = sock->sk;
	net = sk->sk_net;
L
Linus Torvalds 已提交
845
	if (cmd >= SIOCDEVPRIVATE && cmd <= (SIOCDEVPRIVATE + 15)) {
846
		err = dev_ioctl(net, cmd, argp);
L
Linus Torvalds 已提交
847
	} else
848
#ifdef CONFIG_WIRELESS_EXT
L
Linus Torvalds 已提交
849
	if (cmd >= SIOCIWFIRST && cmd <= SIOCIWLAST) {
850
		err = dev_ioctl(net, cmd, argp);
L
Linus Torvalds 已提交
851
	} else
852 853
#endif				/* CONFIG_WIRELESS_EXT */
		switch (cmd) {
L
Linus Torvalds 已提交
854 855 856 857 858 859 860 861 862
		case FIOSETOWN:
		case SIOCSPGRP:
			err = -EFAULT;
			if (get_user(pid, (int __user *)argp))
				break;
			err = f_setown(sock->file, pid, 1);
			break;
		case FIOGETOWN:
		case SIOCGPGRP:
863
			err = put_user(f_getown(sock->file),
864
				       (int __user *)argp);
L
Linus Torvalds 已提交
865 866 867 868 869 870 871 872 873
			break;
		case SIOCGIFBR:
		case SIOCSIFBR:
		case SIOCBRADDBR:
		case SIOCBRDELBR:
			err = -ENOPKG;
			if (!br_ioctl_hook)
				request_module("bridge");

A
Arjan van de Ven 已提交
874
			mutex_lock(&br_ioctl_mutex);
875
			if (br_ioctl_hook)
876
				err = br_ioctl_hook(net, cmd, argp);
A
Arjan van de Ven 已提交
877
			mutex_unlock(&br_ioctl_mutex);
L
Linus Torvalds 已提交
878 879 880 881 882 883 884
			break;
		case SIOCGIFVLAN:
		case SIOCSIFVLAN:
			err = -ENOPKG;
			if (!vlan_ioctl_hook)
				request_module("8021q");

A
Arjan van de Ven 已提交
885
			mutex_lock(&vlan_ioctl_mutex);
L
Linus Torvalds 已提交
886
			if (vlan_ioctl_hook)
887
				err = vlan_ioctl_hook(net, argp);
A
Arjan van de Ven 已提交
888
			mutex_unlock(&vlan_ioctl_mutex);
L
Linus Torvalds 已提交
889 890 891 892 893 894 895 896
			break;
		case SIOCADDDLCI:
		case SIOCDELDLCI:
			err = -ENOPKG;
			if (!dlci_ioctl_hook)
				request_module("dlci");

			if (dlci_ioctl_hook) {
A
Arjan van de Ven 已提交
897
				mutex_lock(&dlci_ioctl_mutex);
L
Linus Torvalds 已提交
898
				err = dlci_ioctl_hook(cmd, argp);
A
Arjan van de Ven 已提交
899
				mutex_unlock(&dlci_ioctl_mutex);
L
Linus Torvalds 已提交
900 901 902 903
			}
			break;
		default:
			err = sock->ops->ioctl(sock, cmd, arg);
904 905 906 907 908 909

			/*
			 * If this ioctl is unknown try to hand it down
			 * to the NIC driver.
			 */
			if (err == -ENOIOCTLCMD)
910
				err = dev_ioctl(net, cmd, argp);
L
Linus Torvalds 已提交
911
			break;
912
		}
L
Linus Torvalds 已提交
913 914 915 916 917 918 919
	return err;
}

int sock_create_lite(int family, int type, int protocol, struct socket **res)
{
	int err;
	struct socket *sock = NULL;
920

L
Linus Torvalds 已提交
921 922 923 924 925 926 927 928 929 930 931
	err = security_socket_create(family, type, protocol, 1);
	if (err)
		goto out;

	sock = sock_alloc();
	if (!sock) {
		err = -ENOMEM;
		goto out;
	}

	sock->type = type;
V
Venkat Yekkirala 已提交
932 933 934 935
	err = security_socket_post_create(sock, family, type, protocol, 1);
	if (err)
		goto out_release;

L
Linus Torvalds 已提交
936 937 938
out:
	*res = sock;
	return err;
V
Venkat Yekkirala 已提交
939 940 941 942
out_release:
	sock_release(sock);
	sock = NULL;
	goto out;
L
Linus Torvalds 已提交
943 944 945
}

/* No kernel lock held - perfect */
946
static unsigned int sock_poll(struct file *file, poll_table *wait)
L
Linus Torvalds 已提交
947 948 949 950
{
	struct socket *sock;

	/*
951
	 *      We can't return errors to poll, so it's either yes or no.
L
Linus Torvalds 已提交
952
	 */
953
	sock = file->private_data;
L
Linus Torvalds 已提交
954 955 956
	return sock->ops->poll(file, sock, wait);
}

957
static int sock_mmap(struct file *file, struct vm_area_struct *vma)
L
Linus Torvalds 已提交
958
{
959
	struct socket *sock = file->private_data;
L
Linus Torvalds 已提交
960 961 962 963

	return sock->ops->mmap(file, sock, vma);
}

964
static int sock_close(struct inode *inode, struct file *filp)
L
Linus Torvalds 已提交
965 966
{
	/*
967 968
	 *      It was possible the inode is NULL we were
	 *      closing an unfinished socket.
L
Linus Torvalds 已提交
969 970
	 */

971
	if (!inode) {
L
Linus Torvalds 已提交
972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996
		printk(KERN_DEBUG "sock_close: NULL inode\n");
		return 0;
	}
	sock_fasync(-1, filp, 0);
	sock_release(SOCKET_I(inode));
	return 0;
}

/*
 *	Update the socket async list
 *
 *	Fasync_list locking strategy.
 *
 *	1. fasync_list is modified only under process context socket lock
 *	   i.e. under semaphore.
 *	2. fasync_list is used under read_lock(&sk->sk_callback_lock)
 *	   or under socket lock.
 *	3. fasync_list can be used from softirq context, so that
 *	   modification under socket lock have to be enhanced with
 *	   write_lock_bh(&sk->sk_callback_lock).
 *							--ANK (990710)
 */

static int sock_fasync(int fd, struct file *filp, int on)
{
997
	struct fasync_struct *fa, *fna = NULL, **prev;
L
Linus Torvalds 已提交
998 999 1000
	struct socket *sock;
	struct sock *sk;

1001
	if (on) {
1002
		fna = kmalloc(sizeof(struct fasync_struct), GFP_KERNEL);
1003
		if (fna == NULL)
L
Linus Torvalds 已提交
1004 1005 1006
			return -ENOMEM;
	}

1007
	sock = filp->private_data;
L
Linus Torvalds 已提交
1008

1009 1010
	sk = sock->sk;
	if (sk == NULL) {
L
Linus Torvalds 已提交
1011 1012 1013 1014 1015 1016
		kfree(fna);
		return -EINVAL;
	}

	lock_sock(sk);

1017
	prev = &(sock->fasync_list);
L
Linus Torvalds 已提交
1018

1019 1020
	for (fa = *prev; fa != NULL; prev = &fa->fa_next, fa = *prev)
		if (fa->fa_file == filp)
L
Linus Torvalds 已提交
1021 1022
			break;

1023 1024
	if (on) {
		if (fa != NULL) {
L
Linus Torvalds 已提交
1025
			write_lock_bh(&sk->sk_callback_lock);
1026
			fa->fa_fd = fd;
L
Linus Torvalds 已提交
1027 1028 1029 1030 1031
			write_unlock_bh(&sk->sk_callback_lock);

			kfree(fna);
			goto out;
		}
1032 1033 1034 1035
		fna->fa_file = filp;
		fna->fa_fd = fd;
		fna->magic = FASYNC_MAGIC;
		fna->fa_next = sock->fasync_list;
L
Linus Torvalds 已提交
1036
		write_lock_bh(&sk->sk_callback_lock);
1037
		sock->fasync_list = fna;
L
Linus Torvalds 已提交
1038
		write_unlock_bh(&sk->sk_callback_lock);
1039 1040
	} else {
		if (fa != NULL) {
L
Linus Torvalds 已提交
1041
			write_lock_bh(&sk->sk_callback_lock);
1042
			*prev = fa->fa_next;
L
Linus Torvalds 已提交
1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058
			write_unlock_bh(&sk->sk_callback_lock);
			kfree(fa);
		}
	}

out:
	release_sock(sock->sk);
	return 0;
}

/* This function may be called only under socket lock or callback_lock */

int sock_wake_async(struct socket *sock, int how, int band)
{
	if (!sock || !sock->fasync_list)
		return -1;
1059
	switch (how) {
L
Linus Torvalds 已提交
1060
	case 1:
1061

L
Linus Torvalds 已提交
1062 1063 1064 1065 1066 1067 1068 1069
		if (test_bit(SOCK_ASYNC_WAITDATA, &sock->flags))
			break;
		goto call_kill;
	case 2:
		if (!test_and_clear_bit(SOCK_ASYNC_NOSPACE, &sock->flags))
			break;
		/* fall through */
	case 0:
1070
call_kill:
L
Linus Torvalds 已提交
1071 1072 1073 1074 1075 1076 1077 1078
		__kill_fasync(sock->fasync_list, SIGIO, band);
		break;
	case 3:
		__kill_fasync(sock->fasync_list, SIGURG, band);
	}
	return 0;
}

1079
static int __sock_create(struct net *net, int family, int type, int protocol,
1080
			 struct socket **res, int kern)
L
Linus Torvalds 已提交
1081 1082 1083
{
	int err;
	struct socket *sock;
1084
	const struct net_proto_family *pf;
L
Linus Torvalds 已提交
1085 1086

	/*
1087
	 *      Check protocol is in range
L
Linus Torvalds 已提交
1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099
	 */
	if (family < 0 || family >= NPROTO)
		return -EAFNOSUPPORT;
	if (type < 0 || type >= SOCK_MAX)
		return -EINVAL;

	/* Compatibility.

	   This uglymoron is moved from INET layer to here to avoid
	   deadlock in module load.
	 */
	if (family == PF_INET && type == SOCK_PACKET) {
1100
		static int warned;
L
Linus Torvalds 已提交
1101 1102
		if (!warned) {
			warned = 1;
1103 1104
			printk(KERN_INFO "%s uses obsolete (PF_INET,SOCK_PACKET)\n",
			       current->comm);
L
Linus Torvalds 已提交
1105 1106 1107 1108 1109 1110 1111
		}
		family = PF_PACKET;
	}

	err = security_socket_create(family, type, protocol, kern);
	if (err)
		return err;
1112

1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127
	/*
	 *	Allocate the socket and allow the family to set things up. if
	 *	the protocol is 0, the family is instructed to select an appropriate
	 *	default.
	 */
	sock = sock_alloc();
	if (!sock) {
		if (net_ratelimit())
			printk(KERN_WARNING "socket: no more sockets\n");
		return -ENFILE;	/* Not exactly a match, but its the
				   closest posix thing */
	}

	sock->type = type;

L
Linus Torvalds 已提交
1128
#if defined(CONFIG_KMOD)
1129 1130 1131
	/* Attempt to load a protocol module if the find failed.
	 *
	 * 12/09/1996 Marcin: But! this makes REALLY only sense, if the user
L
Linus Torvalds 已提交
1132 1133 1134
	 * requested real, full-featured networking support upon configuration.
	 * Otherwise module support will break!
	 */
1135
	if (net_families[family] == NULL)
1136
		request_module("net-pf-%d", family);
L
Linus Torvalds 已提交
1137 1138
#endif

1139 1140 1141 1142 1143
	rcu_read_lock();
	pf = rcu_dereference(net_families[family]);
	err = -EAFNOSUPPORT;
	if (!pf)
		goto out_release;
L
Linus Torvalds 已提交
1144 1145 1146 1147 1148

	/*
	 * We will call the ->create function, that possibly is in a loadable
	 * module, so we have to bump that loadable module refcnt first.
	 */
1149
	if (!try_module_get(pf->owner))
L
Linus Torvalds 已提交
1150 1151
		goto out_release;

1152 1153 1154
	/* Now protected by module ref count */
	rcu_read_unlock();

1155
	err = pf->create(net, sock, protocol);
1156
	if (err < 0)
L
Linus Torvalds 已提交
1157
		goto out_module_put;
1158

L
Linus Torvalds 已提交
1159 1160 1161 1162
	/*
	 * Now to bump the refcnt of the [loadable] module that owns this
	 * socket at sock_release time we decrement its refcnt.
	 */
1163 1164 1165
	if (!try_module_get(sock->ops->owner))
		goto out_module_busy;

L
Linus Torvalds 已提交
1166 1167 1168 1169
	/*
	 * Now that we're done with the ->create function, the [loadable]
	 * module can have its refcnt decremented
	 */
1170
	module_put(pf->owner);
V
Venkat Yekkirala 已提交
1171 1172
	err = security_socket_post_create(sock, family, type, protocol, kern);
	if (err)
1173
		goto out_sock_release;
1174
	*res = sock;
L
Linus Torvalds 已提交
1175

1176 1177 1178 1179
	return 0;

out_module_busy:
	err = -EAFNOSUPPORT;
L
Linus Torvalds 已提交
1180
out_module_put:
1181 1182 1183
	sock->ops = NULL;
	module_put(pf->owner);
out_sock_release:
L
Linus Torvalds 已提交
1184
	sock_release(sock);
1185 1186 1187 1188 1189
	return err;

out_release:
	rcu_read_unlock();
	goto out_sock_release;
L
Linus Torvalds 已提交
1190 1191 1192 1193
}

int sock_create(int family, int type, int protocol, struct socket **res)
{
1194
	return __sock_create(current->nsproxy->net_ns, family, type, protocol, res, 0);
L
Linus Torvalds 已提交
1195 1196 1197 1198
}

int sock_create_kern(int family, int type, int protocol, struct socket **res)
{
1199
	return __sock_create(&init_net, family, type, protocol, res, 1);
L
Linus Torvalds 已提交
1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 1226 1227
}

asmlinkage long sys_socket(int family, int type, int protocol)
{
	int retval;
	struct socket *sock;

	retval = sock_create(family, type, protocol, &sock);
	if (retval < 0)
		goto out;

	retval = sock_map_fd(sock);
	if (retval < 0)
		goto out_release;

out:
	/* It may be already another descriptor 8) Not kernel problem. */
	return retval;

out_release:
	sock_release(sock);
	return retval;
}

/*
 *	Create a pair of connected sockets.
 */

1228 1229
asmlinkage long sys_socketpair(int family, int type, int protocol,
			       int __user *usockvec)
L
Linus Torvalds 已提交
1230 1231 1232
{
	struct socket *sock1, *sock2;
	int fd1, fd2, err;
A
Al Viro 已提交
1233
	struct file *newfile1, *newfile2;
L
Linus Torvalds 已提交
1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248

	/*
	 * Obtain the first socket and check if the underlying protocol
	 * supports the socketpair call.
	 */

	err = sock_create(family, type, protocol, &sock1);
	if (err < 0)
		goto out;

	err = sock_create(family, type, protocol, &sock2);
	if (err < 0)
		goto out_release_1;

	err = sock1->ops->socketpair(sock1, sock2);
1249
	if (err < 0)
L
Linus Torvalds 已提交
1250 1251
		goto out_release_both;

A
Al Viro 已提交
1252
	fd1 = sock_alloc_fd(&newfile1);
1253 1254
	if (unlikely(fd1 < 0)) {
		err = fd1;
A
Al Viro 已提交
1255
		goto out_release_both;
1256
	}
L
Linus Torvalds 已提交
1257

A
Al Viro 已提交
1258 1259
	fd2 = sock_alloc_fd(&newfile2);
	if (unlikely(fd2 < 0)) {
1260
		err = fd2;
A
Al Viro 已提交
1261 1262
		put_filp(newfile1);
		put_unused_fd(fd1);
L
Linus Torvalds 已提交
1263
		goto out_release_both;
A
Al Viro 已提交
1264
	}
L
Linus Torvalds 已提交
1265

A
Al Viro 已提交
1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282
	err = sock_attach_fd(sock1, newfile1);
	if (unlikely(err < 0)) {
		goto out_fd2;
	}

	err = sock_attach_fd(sock2, newfile2);
	if (unlikely(err < 0)) {
		fput(newfile1);
		goto out_fd1;
	}

	err = audit_fd_pair(fd1, fd2);
	if (err < 0) {
		fput(newfile1);
		fput(newfile2);
		goto out_fd;
	}
L
Linus Torvalds 已提交
1283

A
Al Viro 已提交
1284 1285
	fd_install(fd1, newfile1);
	fd_install(fd2, newfile2);
L
Linus Torvalds 已提交
1286 1287 1288 1289
	/* fd1 and fd2 may be already another descriptors.
	 * Not kernel problem.
	 */

1290
	err = put_user(fd1, &usockvec[0]);
L
Linus Torvalds 已提交
1291 1292 1293 1294 1295 1296 1297 1298 1299 1300
	if (!err)
		err = put_user(fd2, &usockvec[1]);
	if (!err)
		return 0;

	sys_close(fd2);
	sys_close(fd1);
	return err;

out_release_both:
1301
	sock_release(sock2);
L
Linus Torvalds 已提交
1302
out_release_1:
1303
	sock_release(sock1);
L
Linus Torvalds 已提交
1304 1305
out:
	return err;
A
Al Viro 已提交
1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316

out_fd2:
	put_filp(newfile1);
	sock_release(sock1);
out_fd1:
	put_filp(newfile2);
	sock_release(sock2);
out_fd:
	put_unused_fd(fd1);
	put_unused_fd(fd2);
	goto out;
L
Linus Torvalds 已提交
1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330
}

/*
 *	Bind a name to a socket. Nothing much to do here since it's
 *	the protocol's responsibility to handle the local address.
 *
 *	We move the socket address to kernel space before we call
 *	the protocol layer (having also checked the address is ok).
 */

asmlinkage long sys_bind(int fd, struct sockaddr __user *umyaddr, int addrlen)
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
1331
	int err, fput_needed;
L
Linus Torvalds 已提交
1332

1333
	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1334
	if (sock) {
1335 1336 1337 1338 1339
		err = move_addr_to_kernel(umyaddr, addrlen, address);
		if (err >= 0) {
			err = security_socket_bind(sock,
						   (struct sockaddr *)address,
						   addrlen);
1340 1341
			if (!err)
				err = sock->ops->bind(sock,
1342 1343
						      (struct sockaddr *)
						      address, addrlen);
L
Linus Torvalds 已提交
1344
		}
1345
		fput_light(sock->file, fput_needed);
1346
	}
L
Linus Torvalds 已提交
1347 1348 1349 1350 1351 1352 1353 1354 1355
	return err;
}

/*
 *	Perform a listen. Basically, we allow the protocol to do anything
 *	necessary for a listen, and if that works, we mark the socket as
 *	ready for listening.
 */

1356
int sysctl_somaxconn __read_mostly = SOMAXCONN;
L
Linus Torvalds 已提交
1357 1358 1359 1360

asmlinkage long sys_listen(int fd, int backlog)
{
	struct socket *sock;
1361
	int err, fput_needed;
1362 1363 1364 1365

	sock = sockfd_lookup_light(fd, &err, &fput_needed);
	if (sock) {
		if ((unsigned)backlog > sysctl_somaxconn)
L
Linus Torvalds 已提交
1366 1367 1368
			backlog = sysctl_somaxconn;

		err = security_socket_listen(sock, backlog);
1369 1370
		if (!err)
			err = sock->ops->listen(sock, backlog);
L
Linus Torvalds 已提交
1371

1372
		fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1373 1374 1375 1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388
	}
	return err;
}

/*
 *	For accept, we attempt to create a new socket, set up the link
 *	with the client, wake up the client, then return the new
 *	connected fd. We collect the address of the connector in kernel
 *	space and move it to user at the very end. This is unclean because
 *	we open the socket then return an error.
 *
 *	1003.1g adds the ability to recvmsg() to query connection pending
 *	status to recvmsg. We need to add that support in a way thats
 *	clean when we restucture accept also.
 */

1389 1390
asmlinkage long sys_accept(int fd, struct sockaddr __user *upeer_sockaddr,
			   int __user *upeer_addrlen)
L
Linus Torvalds 已提交
1391 1392
{
	struct socket *sock, *newsock;
1393
	struct file *newfile;
1394
	int err, len, newfd, fput_needed;
L
Linus Torvalds 已提交
1395 1396
	char address[MAX_SOCK_ADDR];

1397
	sock = sockfd_lookup_light(fd, &err, &fput_needed);
L
Linus Torvalds 已提交
1398 1399 1400 1401
	if (!sock)
		goto out;

	err = -ENFILE;
1402
	if (!(newsock = sock_alloc()))
L
Linus Torvalds 已提交
1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413
		goto out_put;

	newsock->type = sock->type;
	newsock->ops = sock->ops;

	/*
	 * We don't need try_module_get here, as the listening socket (sock)
	 * has the protocol module (sock->ops->owner) held.
	 */
	__module_get(newsock->ops->owner);

1414 1415 1416
	newfd = sock_alloc_fd(&newfile);
	if (unlikely(newfd < 0)) {
		err = newfd;
1417 1418
		sock_release(newsock);
		goto out_put;
1419 1420 1421 1422
	}

	err = sock_attach_fd(newsock, newfile);
	if (err < 0)
1423
		goto out_fd_simple;
1424

1425 1426
	err = security_socket_accept(sock, newsock);
	if (err)
1427
		goto out_fd;
1428

L
Linus Torvalds 已提交
1429 1430
	err = sock->ops->accept(sock, newsock, sock->file->f_flags);
	if (err < 0)
1431
		goto out_fd;
L
Linus Torvalds 已提交
1432 1433

	if (upeer_sockaddr) {
1434 1435
		if (newsock->ops->getname(newsock, (struct sockaddr *)address,
					  &len, 2) < 0) {
L
Linus Torvalds 已提交
1436
			err = -ECONNABORTED;
1437
			goto out_fd;
L
Linus Torvalds 已提交
1438
		}
1439 1440
		err = move_addr_to_user(address, len, upeer_sockaddr,
					upeer_addrlen);
L
Linus Torvalds 已提交
1441
		if (err < 0)
1442
			goto out_fd;
L
Linus Torvalds 已提交
1443 1444 1445 1446
	}

	/* File flags are not inherited via accept() unlike another OSes. */

1447 1448
	fd_install(newfd, newfile);
	err = newfd;
L
Linus Torvalds 已提交
1449 1450 1451 1452

	security_socket_post_accept(sock, newsock);

out_put:
1453
	fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1454 1455
out:
	return err;
1456 1457 1458 1459 1460
out_fd_simple:
	sock_release(newsock);
	put_filp(newfile);
	put_unused_fd(newfd);
	goto out_put;
1461
out_fd:
1462
	fput(newfile);
1463
	put_unused_fd(newfd);
L
Linus Torvalds 已提交
1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478
	goto out_put;
}

/*
 *	Attempt to connect to a socket with the server address.  The address
 *	is in user space so we verify it is OK and move it to kernel space.
 *
 *	For 1003.1g we need to add clean support for a bind to AF_UNSPEC to
 *	break bindings
 *
 *	NOTE: 1003.1g draft 6.3 is broken with respect to AX.25/NetROM and
 *	other SEQPACKET protocols that take time to connect() as it doesn't
 *	include the -EINPROGRESS status for such sockets.
 */

1479 1480
asmlinkage long sys_connect(int fd, struct sockaddr __user *uservaddr,
			    int addrlen)
L
Linus Torvalds 已提交
1481 1482 1483
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
1484
	int err, fput_needed;
L
Linus Torvalds 已提交
1485

1486
	sock = sockfd_lookup_light(fd, &err, &fput_needed);
L
Linus Torvalds 已提交
1487 1488 1489 1490 1491 1492
	if (!sock)
		goto out;
	err = move_addr_to_kernel(uservaddr, addrlen, address);
	if (err < 0)
		goto out_put;

1493 1494
	err =
	    security_socket_connect(sock, (struct sockaddr *)address, addrlen);
L
Linus Torvalds 已提交
1495 1496 1497
	if (err)
		goto out_put;

1498
	err = sock->ops->connect(sock, (struct sockaddr *)address, addrlen,
L
Linus Torvalds 已提交
1499 1500
				 sock->file->f_flags);
out_put:
1501
	fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1502 1503 1504 1505 1506 1507 1508 1509 1510
out:
	return err;
}

/*
 *	Get the local address ('name') of a socket object. Move the obtained
 *	name to user space.
 */

1511 1512
asmlinkage long sys_getsockname(int fd, struct sockaddr __user *usockaddr,
				int __user *usockaddr_len)
L
Linus Torvalds 已提交
1513 1514 1515
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
1516
	int len, err, fput_needed;
1517

1518
	sock = sockfd_lookup_light(fd, &err, &fput_needed);
L
Linus Torvalds 已提交
1519 1520 1521 1522 1523 1524 1525 1526 1527 1528 1529 1530 1531
	if (!sock)
		goto out;

	err = security_socket_getsockname(sock);
	if (err)
		goto out_put;

	err = sock->ops->getname(sock, (struct sockaddr *)address, &len, 0);
	if (err)
		goto out_put;
	err = move_addr_to_user(address, len, usockaddr, usockaddr_len);

out_put:
1532
	fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1533 1534 1535 1536 1537 1538 1539 1540 1541
out:
	return err;
}

/*
 *	Get the remote address ('name') of a socket object. Move the obtained
 *	name to user space.
 */

1542 1543
asmlinkage long sys_getpeername(int fd, struct sockaddr __user *usockaddr,
				int __user *usockaddr_len)
L
Linus Torvalds 已提交
1544 1545 1546
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
1547
	int len, err, fput_needed;
L
Linus Torvalds 已提交
1548

1549 1550
	sock = sockfd_lookup_light(fd, &err, &fput_needed);
	if (sock != NULL) {
L
Linus Torvalds 已提交
1551 1552
		err = security_socket_getpeername(sock);
		if (err) {
1553
			fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1554 1555 1556
			return err;
		}

1557 1558 1559
		err =
		    sock->ops->getname(sock, (struct sockaddr *)address, &len,
				       1);
L
Linus Torvalds 已提交
1560
		if (!err)
1561 1562
			err = move_addr_to_user(address, len, usockaddr,
						usockaddr_len);
1563
		fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1564 1565 1566 1567 1568 1569 1570 1571 1572 1573
	}
	return err;
}

/*
 *	Send a datagram to a given address. We move the address into kernel
 *	space and check the user space data area is readable before invoking
 *	the protocol.
 */

1574 1575 1576
asmlinkage long sys_sendto(int fd, void __user *buff, size_t len,
			   unsigned flags, struct sockaddr __user *addr,
			   int addr_len)
L
Linus Torvalds 已提交
1577 1578 1579 1580 1581 1582
{
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
	int err;
	struct msghdr msg;
	struct iovec iov;
1583 1584 1585 1586
	int fput_needed;
	struct file *sock_file;

	sock_file = fget_light(fd, &fput_needed);
1587
	err = -EBADF;
1588
	if (!sock_file)
1589
		goto out;
1590 1591

	sock = sock_from_file(sock_file, &err);
L
Linus Torvalds 已提交
1592
	if (!sock)
1593
		goto out_put;
1594 1595 1596 1597 1598 1599 1600 1601
	iov.iov_base = buff;
	iov.iov_len = len;
	msg.msg_name = NULL;
	msg.msg_iov = &iov;
	msg.msg_iovlen = 1;
	msg.msg_control = NULL;
	msg.msg_controllen = 0;
	msg.msg_namelen = 0;
1602
	if (addr) {
L
Linus Torvalds 已提交
1603 1604 1605
		err = move_addr_to_kernel(addr, addr_len, address);
		if (err < 0)
			goto out_put;
1606 1607
		msg.msg_name = address;
		msg.msg_namelen = addr_len;
L
Linus Torvalds 已提交
1608 1609 1610 1611 1612 1613
	}
	if (sock->file->f_flags & O_NONBLOCK)
		flags |= MSG_DONTWAIT;
	msg.msg_flags = flags;
	err = sock_sendmsg(sock, &msg, len);

1614
out_put:
1615
	fput_light(sock_file, fput_needed);
1616
out:
L
Linus Torvalds 已提交
1617 1618 1619 1620
	return err;
}

/*
1621
 *	Send a datagram down a socket.
L
Linus Torvalds 已提交
1622 1623
 */

1624
asmlinkage long sys_send(int fd, void __user *buff, size_t len, unsigned flags)
L
Linus Torvalds 已提交
1625 1626 1627 1628 1629
{
	return sys_sendto(fd, buff, len, flags, NULL, 0);
}

/*
1630
 *	Receive a frame from the socket and optionally record the address of the
L
Linus Torvalds 已提交
1631 1632 1633 1634
 *	sender. We verify the buffers are writable and if needed move the
 *	sender address from kernel to user space.
 */

1635 1636 1637
asmlinkage long sys_recvfrom(int fd, void __user *ubuf, size_t size,
			     unsigned flags, struct sockaddr __user *addr,
			     int __user *addr_len)
L
Linus Torvalds 已提交
1638 1639 1640 1641 1642
{
	struct socket *sock;
	struct iovec iov;
	struct msghdr msg;
	char address[MAX_SOCK_ADDR];
1643
	int err, err2;
1644 1645 1646 1647
	struct file *sock_file;
	int fput_needed;

	sock_file = fget_light(fd, &fput_needed);
1648
	err = -EBADF;
1649
	if (!sock_file)
1650
		goto out;
L
Linus Torvalds 已提交
1651

1652
	sock = sock_from_file(sock_file, &err);
L
Linus Torvalds 已提交
1653
	if (!sock)
1654
		goto out_put;
L
Linus Torvalds 已提交
1655

1656 1657 1658 1659 1660 1661 1662 1663
	msg.msg_control = NULL;
	msg.msg_controllen = 0;
	msg.msg_iovlen = 1;
	msg.msg_iov = &iov;
	iov.iov_len = size;
	iov.iov_base = ubuf;
	msg.msg_name = address;
	msg.msg_namelen = MAX_SOCK_ADDR;
L
Linus Torvalds 已提交
1664 1665
	if (sock->file->f_flags & O_NONBLOCK)
		flags |= MSG_DONTWAIT;
1666
	err = sock_recvmsg(sock, &msg, size, flags);
L
Linus Torvalds 已提交
1667

1668 1669 1670 1671
	if (err >= 0 && addr != NULL) {
		err2 = move_addr_to_user(address, msg.msg_namelen, addr, addr_len);
		if (err2 < 0)
			err = err2;
L
Linus Torvalds 已提交
1672
	}
1673
out_put:
1674
	fput_light(sock_file, fput_needed);
1675
out:
L
Linus Torvalds 已提交
1676 1677 1678 1679
	return err;
}

/*
1680
 *	Receive a datagram from a socket.
L
Linus Torvalds 已提交
1681 1682
 */

1683 1684
asmlinkage long sys_recv(int fd, void __user *ubuf, size_t size,
			 unsigned flags)
L
Linus Torvalds 已提交
1685 1686 1687 1688 1689 1690 1691 1692 1693
{
	return sys_recvfrom(fd, ubuf, size, flags, NULL, NULL);
}

/*
 *	Set a socket option. Because we don't know the option lengths we have
 *	to pass the user mode parameter for the protocols to sort out.
 */

1694 1695
asmlinkage long sys_setsockopt(int fd, int level, int optname,
			       char __user *optval, int optlen)
L
Linus Torvalds 已提交
1696
{
1697
	int err, fput_needed;
L
Linus Torvalds 已提交
1698 1699 1700 1701
	struct socket *sock;

	if (optlen < 0)
		return -EINVAL;
1702 1703 1704 1705

	sock = sockfd_lookup_light(fd, &err, &fput_needed);
	if (sock != NULL) {
		err = security_socket_setsockopt(sock, level, optname);
1706 1707
		if (err)
			goto out_put;
L
Linus Torvalds 已提交
1708 1709

		if (level == SOL_SOCKET)
1710 1711 1712
			err =
			    sock_setsockopt(sock, level, optname, optval,
					    optlen);
L
Linus Torvalds 已提交
1713
		else
1714 1715 1716
			err =
			    sock->ops->setsockopt(sock, level, optname, optval,
						  optlen);
1717 1718
out_put:
		fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1719 1720 1721 1722 1723 1724 1725 1726 1727
	}
	return err;
}

/*
 *	Get a socket option. Because we don't know the option lengths we have
 *	to pass a user mode parameter for the protocols to sort out.
 */

1728 1729
asmlinkage long sys_getsockopt(int fd, int level, int optname,
			       char __user *optval, int __user *optlen)
L
Linus Torvalds 已提交
1730
{
1731
	int err, fput_needed;
L
Linus Torvalds 已提交
1732 1733
	struct socket *sock;

1734 1735
	sock = sockfd_lookup_light(fd, &err, &fput_needed);
	if (sock != NULL) {
1736 1737 1738
		err = security_socket_getsockopt(sock, level, optname);
		if (err)
			goto out_put;
L
Linus Torvalds 已提交
1739 1740

		if (level == SOL_SOCKET)
1741 1742 1743
			err =
			    sock_getsockopt(sock, level, optname, optval,
					    optlen);
L
Linus Torvalds 已提交
1744
		else
1745 1746 1747
			err =
			    sock->ops->getsockopt(sock, level, optname, optval,
						  optlen);
1748 1749
out_put:
		fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1750 1751 1752 1753 1754 1755 1756 1757 1758 1759
	}
	return err;
}

/*
 *	Shutdown a socket.
 */

asmlinkage long sys_shutdown(int fd, int how)
{
1760
	int err, fput_needed;
L
Linus Torvalds 已提交
1761 1762
	struct socket *sock;

1763 1764
	sock = sockfd_lookup_light(fd, &err, &fput_needed);
	if (sock != NULL) {
L
Linus Torvalds 已提交
1765
		err = security_socket_shutdown(sock, how);
1766 1767 1768
		if (!err)
			err = sock->ops->shutdown(sock, how);
		fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1769 1770 1771 1772
	}
	return err;
}

1773
/* A couple of helpful macros for getting the address of the 32/64 bit
L
Linus Torvalds 已提交
1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785
 * fields which are the same type (int / unsigned) on our platforms.
 */
#define COMPAT_MSG(msg, member)	((MSG_CMSG_COMPAT & flags) ? &msg##_compat->member : &msg->member)
#define COMPAT_NAMELEN(msg)	COMPAT_MSG(msg, msg_namelen)
#define COMPAT_FLAGS(msg)	COMPAT_MSG(msg, msg_flags)

/*
 *	BSD sendmsg interface
 */

asmlinkage long sys_sendmsg(int fd, struct msghdr __user *msg, unsigned flags)
{
1786 1787
	struct compat_msghdr __user *msg_compat =
	    (struct compat_msghdr __user *)msg;
L
Linus Torvalds 已提交
1788 1789 1790
	struct socket *sock;
	char address[MAX_SOCK_ADDR];
	struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
1791
	unsigned char ctl[sizeof(struct cmsghdr) + 20]
1792 1793
	    __attribute__ ((aligned(sizeof(__kernel_size_t))));
	/* 20 is size of ipv6_pktinfo */
L
Linus Torvalds 已提交
1794 1795 1796
	unsigned char *ctl_buf = ctl;
	struct msghdr msg_sys;
	int err, ctl_len, iov_size, total_len;
1797
	int fput_needed;
1798

L
Linus Torvalds 已提交
1799 1800 1801 1802
	err = -EFAULT;
	if (MSG_CMSG_COMPAT & flags) {
		if (get_compat_msghdr(&msg_sys, msg_compat))
			return -EFAULT;
1803 1804
	}
	else if (copy_from_user(&msg_sys, msg, sizeof(struct msghdr)))
L
Linus Torvalds 已提交
1805 1806
		return -EFAULT;

1807
	sock = sockfd_lookup_light(fd, &err, &fput_needed);
1808
	if (!sock)
L
Linus Torvalds 已提交
1809 1810 1811 1812 1813 1814 1815
		goto out;

	/* do not move before msg_sys is valid */
	err = -EMSGSIZE;
	if (msg_sys.msg_iovlen > UIO_MAXIOV)
		goto out_put;

1816
	/* Check whether to allocate the iovec area */
L
Linus Torvalds 已提交
1817 1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829
	err = -ENOMEM;
	iov_size = msg_sys.msg_iovlen * sizeof(struct iovec);
	if (msg_sys.msg_iovlen > UIO_FASTIOV) {
		iov = sock_kmalloc(sock->sk, iov_size, GFP_KERNEL);
		if (!iov)
			goto out_put;
	}

	/* This will also move the address data into kernel space */
	if (MSG_CMSG_COMPAT & flags) {
		err = verify_compat_iovec(&msg_sys, iov, address, VERIFY_READ);
	} else
		err = verify_iovec(&msg_sys, iov, address, VERIFY_READ);
1830
	if (err < 0)
L
Linus Torvalds 已提交
1831 1832 1833 1834 1835 1836 1837
		goto out_freeiov;
	total_len = err;

	err = -ENOBUFS;

	if (msg_sys.msg_controllen > INT_MAX)
		goto out_freeiov;
1838
	ctl_len = msg_sys.msg_controllen;
L
Linus Torvalds 已提交
1839
	if ((MSG_CMSG_COMPAT & flags) && ctl_len) {
1840 1841 1842
		err =
		    cmsghdr_from_user_compat_to_kern(&msg_sys, sock->sk, ctl,
						     sizeof(ctl));
L
Linus Torvalds 已提交
1843 1844 1845
		if (err)
			goto out_freeiov;
		ctl_buf = msg_sys.msg_control;
A
Al Viro 已提交
1846
		ctl_len = msg_sys.msg_controllen;
L
Linus Torvalds 已提交
1847
	} else if (ctl_len) {
1848
		if (ctl_len > sizeof(ctl)) {
L
Linus Torvalds 已提交
1849
			ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL);
1850
			if (ctl_buf == NULL)
L
Linus Torvalds 已提交
1851 1852 1853 1854 1855 1856 1857 1858
				goto out_freeiov;
		}
		err = -EFAULT;
		/*
		 * Careful! Before this, msg_sys.msg_control contains a user pointer.
		 * Afterwards, it will be a kernel pointer. Thus the compiler-assisted
		 * checking falls down on this.
		 */
1859 1860
		if (copy_from_user(ctl_buf, (void __user *)msg_sys.msg_control,
				   ctl_len))
L
Linus Torvalds 已提交
1861 1862 1863 1864 1865 1866 1867 1868 1869 1870
			goto out_freectl;
		msg_sys.msg_control = ctl_buf;
	}
	msg_sys.msg_flags = flags;

	if (sock->file->f_flags & O_NONBLOCK)
		msg_sys.msg_flags |= MSG_DONTWAIT;
	err = sock_sendmsg(sock, &msg_sys, total_len);

out_freectl:
1871
	if (ctl_buf != ctl)
L
Linus Torvalds 已提交
1872 1873 1874 1875 1876
		sock_kfree_s(sock->sk, ctl_buf, ctl_len);
out_freeiov:
	if (iov != iovstack)
		sock_kfree_s(sock->sk, iov, iov_size);
out_put:
1877
	fput_light(sock->file, fput_needed);
1878
out:
L
Linus Torvalds 已提交
1879 1880 1881 1882 1883 1884 1885
	return err;
}

/*
 *	BSD recvmsg interface
 */

1886 1887
asmlinkage long sys_recvmsg(int fd, struct msghdr __user *msg,
			    unsigned int flags)
L
Linus Torvalds 已提交
1888
{
1889 1890
	struct compat_msghdr __user *msg_compat =
	    (struct compat_msghdr __user *)msg;
L
Linus Torvalds 已提交
1891 1892
	struct socket *sock;
	struct iovec iovstack[UIO_FASTIOV];
1893
	struct iovec *iov = iovstack;
L
Linus Torvalds 已提交
1894 1895 1896
	struct msghdr msg_sys;
	unsigned long cmsg_ptr;
	int err, iov_size, total_len, len;
1897
	int fput_needed;
L
Linus Torvalds 已提交
1898 1899 1900 1901 1902 1903 1904

	/* kernel mode address */
	char addr[MAX_SOCK_ADDR];

	/* user mode address pointers */
	struct sockaddr __user *uaddr;
	int __user *uaddr_len;
1905

L
Linus Torvalds 已提交
1906 1907 1908
	if (MSG_CMSG_COMPAT & flags) {
		if (get_compat_msghdr(&msg_sys, msg_compat))
			return -EFAULT;
1909 1910 1911
	}
	else if (copy_from_user(&msg_sys, msg, sizeof(struct msghdr)))
		return -EFAULT;
L
Linus Torvalds 已提交
1912

1913
	sock = sockfd_lookup_light(fd, &err, &fput_needed);
L
Linus Torvalds 已提交
1914 1915 1916 1917 1918 1919
	if (!sock)
		goto out;

	err = -EMSGSIZE;
	if (msg_sys.msg_iovlen > UIO_MAXIOV)
		goto out_put;
1920 1921

	/* Check whether to allocate the iovec area */
L
Linus Torvalds 已提交
1922 1923 1924 1925 1926 1927 1928 1929 1930
	err = -ENOMEM;
	iov_size = msg_sys.msg_iovlen * sizeof(struct iovec);
	if (msg_sys.msg_iovlen > UIO_FASTIOV) {
		iov = sock_kmalloc(sock->sk, iov_size, GFP_KERNEL);
		if (!iov)
			goto out_put;
	}

	/*
1931 1932
	 *      Save the user-mode address (verify_iovec will change the
	 *      kernel msghdr to use the kernel address space)
L
Linus Torvalds 已提交
1933
	 */
1934

S
Stephen Hemminger 已提交
1935
	uaddr = (__force void __user *)msg_sys.msg_name;
L
Linus Torvalds 已提交
1936 1937 1938 1939 1940 1941 1942
	uaddr_len = COMPAT_NAMELEN(msg);
	if (MSG_CMSG_COMPAT & flags) {
		err = verify_compat_iovec(&msg_sys, iov, addr, VERIFY_WRITE);
	} else
		err = verify_iovec(&msg_sys, iov, addr, VERIFY_WRITE);
	if (err < 0)
		goto out_freeiov;
1943
	total_len = err;
L
Linus Torvalds 已提交
1944 1945

	cmsg_ptr = (unsigned long)msg_sys.msg_control;
U
Ulrich Drepper 已提交
1946
	msg_sys.msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT);
1947

L
Linus Torvalds 已提交
1948 1949 1950 1951 1952 1953 1954 1955
	if (sock->file->f_flags & O_NONBLOCK)
		flags |= MSG_DONTWAIT;
	err = sock_recvmsg(sock, &msg_sys, total_len, flags);
	if (err < 0)
		goto out_freeiov;
	len = err;

	if (uaddr != NULL) {
1956 1957
		err = move_addr_to_user(addr, msg_sys.msg_namelen, uaddr,
					uaddr_len);
L
Linus Torvalds 已提交
1958 1959 1960
		if (err < 0)
			goto out_freeiov;
	}
1961 1962
	err = __put_user((msg_sys.msg_flags & ~MSG_CMSG_COMPAT),
			 COMPAT_FLAGS(msg));
L
Linus Torvalds 已提交
1963 1964 1965
	if (err)
		goto out_freeiov;
	if (MSG_CMSG_COMPAT & flags)
1966
		err = __put_user((unsigned long)msg_sys.msg_control - cmsg_ptr,
L
Linus Torvalds 已提交
1967 1968
				 &msg_compat->msg_controllen);
	else
1969
		err = __put_user((unsigned long)msg_sys.msg_control - cmsg_ptr,
L
Linus Torvalds 已提交
1970 1971 1972 1973 1974 1975 1976 1977 1978
				 &msg->msg_controllen);
	if (err)
		goto out_freeiov;
	err = len;

out_freeiov:
	if (iov != iovstack)
		sock_kfree_s(sock->sk, iov, iov_size);
out_put:
1979
	fput_light(sock->file, fput_needed);
L
Linus Torvalds 已提交
1980 1981 1982 1983 1984 1985 1986 1987
out:
	return err;
}

#ifdef __ARCH_WANT_SYS_SOCKETCALL

/* Argument list sizes for sys_socketcall */
#define AL(x) ((x) * sizeof(unsigned long))
1988 1989 1990 1991 1992 1993
static const unsigned char nargs[18]={
	AL(0),AL(3),AL(3),AL(3),AL(2),AL(3),
	AL(3),AL(3),AL(4),AL(4),AL(4),AL(6),
	AL(6),AL(2),AL(5),AL(5),AL(3),AL(3)
};

L
Linus Torvalds 已提交
1994 1995 1996
#undef AL

/*
1997
 *	System call vectors.
L
Linus Torvalds 已提交
1998 1999 2000
 *
 *	Argument checking cleaned up. Saved 20% in size.
 *  This function doesn't need to set the kernel lock because
2001
 *  it is set by the callees.
L
Linus Torvalds 已提交
2002 2003 2004 2005 2006
 */

asmlinkage long sys_socketcall(int call, unsigned long __user *args)
{
	unsigned long a[6];
2007
	unsigned long a0, a1;
L
Linus Torvalds 已提交
2008 2009
	int err;

2010
	if (call < 1 || call > SYS_RECVMSG)
L
Linus Torvalds 已提交
2011 2012 2013 2014 2015
		return -EINVAL;

	/* copy_from_user should be SMP safe. */
	if (copy_from_user(a, args, nargs[call]))
		return -EFAULT;
2016

2017
	err = audit_socketcall(nargs[call] / sizeof(unsigned long), a);
2018 2019 2020
	if (err)
		return err;

2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089
	a0 = a[0];
	a1 = a[1];

	switch (call) {
	case SYS_SOCKET:
		err = sys_socket(a0, a1, a[2]);
		break;
	case SYS_BIND:
		err = sys_bind(a0, (struct sockaddr __user *)a1, a[2]);
		break;
	case SYS_CONNECT:
		err = sys_connect(a0, (struct sockaddr __user *)a1, a[2]);
		break;
	case SYS_LISTEN:
		err = sys_listen(a0, a1);
		break;
	case SYS_ACCEPT:
		err =
		    sys_accept(a0, (struct sockaddr __user *)a1,
			       (int __user *)a[2]);
		break;
	case SYS_GETSOCKNAME:
		err =
		    sys_getsockname(a0, (struct sockaddr __user *)a1,
				    (int __user *)a[2]);
		break;
	case SYS_GETPEERNAME:
		err =
		    sys_getpeername(a0, (struct sockaddr __user *)a1,
				    (int __user *)a[2]);
		break;
	case SYS_SOCKETPAIR:
		err = sys_socketpair(a0, a1, a[2], (int __user *)a[3]);
		break;
	case SYS_SEND:
		err = sys_send(a0, (void __user *)a1, a[2], a[3]);
		break;
	case SYS_SENDTO:
		err = sys_sendto(a0, (void __user *)a1, a[2], a[3],
				 (struct sockaddr __user *)a[4], a[5]);
		break;
	case SYS_RECV:
		err = sys_recv(a0, (void __user *)a1, a[2], a[3]);
		break;
	case SYS_RECVFROM:
		err = sys_recvfrom(a0, (void __user *)a1, a[2], a[3],
				   (struct sockaddr __user *)a[4],
				   (int __user *)a[5]);
		break;
	case SYS_SHUTDOWN:
		err = sys_shutdown(a0, a1);
		break;
	case SYS_SETSOCKOPT:
		err = sys_setsockopt(a0, a1, a[2], (char __user *)a[3], a[4]);
		break;
	case SYS_GETSOCKOPT:
		err =
		    sys_getsockopt(a0, a1, a[2], (char __user *)a[3],
				   (int __user *)a[4]);
		break;
	case SYS_SENDMSG:
		err = sys_sendmsg(a0, (struct msghdr __user *)a1, a[2]);
		break;
	case SYS_RECVMSG:
		err = sys_recvmsg(a0, (struct msghdr __user *)a1, a[2]);
		break;
	default:
		err = -EINVAL;
		break;
L
Linus Torvalds 已提交
2090 2091 2092 2093
	}
	return err;
}

2094
#endif				/* __ARCH_WANT_SYS_SOCKETCALL */
L
Linus Torvalds 已提交
2095

2096 2097 2098 2099
/**
 *	sock_register - add a socket protocol handler
 *	@ops: description of protocol
 *
L
Linus Torvalds 已提交
2100 2101
 *	This function is called by a protocol handler that wants to
 *	advertise its address family, and have it linked into the
2102 2103
 *	socket interface. The value ops->family coresponds to the
 *	socket system call protocol family.
L
Linus Torvalds 已提交
2104
 */
2105
int sock_register(const struct net_proto_family *ops)
L
Linus Torvalds 已提交
2106 2107 2108 2109
{
	int err;

	if (ops->family >= NPROTO) {
2110 2111
		printk(KERN_CRIT "protocol %d >= NPROTO(%d)\n", ops->family,
		       NPROTO);
L
Linus Torvalds 已提交
2112 2113
		return -ENOBUFS;
	}
2114 2115 2116 2117 2118

	spin_lock(&net_family_lock);
	if (net_families[ops->family])
		err = -EEXIST;
	else {
2119
		net_families[ops->family] = ops;
L
Linus Torvalds 已提交
2120 2121
		err = 0;
	}
2122 2123
	spin_unlock(&net_family_lock);

2124
	printk(KERN_INFO "NET: Registered protocol family %d\n", ops->family);
L
Linus Torvalds 已提交
2125 2126 2127
	return err;
}

2128 2129 2130 2131
/**
 *	sock_unregister - remove a protocol handler
 *	@family: protocol family to remove
 *
L
Linus Torvalds 已提交
2132 2133
 *	This function is called by a protocol handler that wants to
 *	remove its address family, and have it unlinked from the
2134 2135 2136 2137 2138 2139
 *	new socket creation.
 *
 *	If protocol handler is a module, then it can use module reference
 *	counts to protect against new references. If protocol handler is not
 *	a module then it needs to provide its own protection in
 *	the ops->create routine.
L
Linus Torvalds 已提交
2140
 */
2141
void sock_unregister(int family)
L
Linus Torvalds 已提交
2142
{
2143
	BUG_ON(family < 0 || family >= NPROTO);
L
Linus Torvalds 已提交
2144

2145
	spin_lock(&net_family_lock);
2146
	net_families[family] = NULL;
2147 2148 2149 2150
	spin_unlock(&net_family_lock);

	synchronize_rcu();

2151
	printk(KERN_INFO "NET: Unregistered protocol family %d\n", family);
L
Linus Torvalds 已提交
2152 2153
}

2154
static int __init sock_init(void)
L
Linus Torvalds 已提交
2155 2156
{
	/*
2157
	 *      Initialize sock SLAB cache.
L
Linus Torvalds 已提交
2158
	 */
2159

L
Linus Torvalds 已提交
2160 2161 2162
	sk_init();

	/*
2163
	 *      Initialize skbuff SLAB cache
L
Linus Torvalds 已提交
2164 2165 2166 2167
	 */
	skb_init();

	/*
2168
	 *      Initialize the protocols module.
L
Linus Torvalds 已提交
2169 2170 2171 2172 2173
	 */

	init_inodecache();
	register_filesystem(&sock_fs_type);
	sock_mnt = kern_mount(&sock_fs_type);
2174 2175

	/* The real protocol initialization is performed in later initcalls.
L
Linus Torvalds 已提交
2176 2177 2178 2179 2180
	 */

#ifdef CONFIG_NETFILTER
	netfilter_init();
#endif
2181 2182

	return 0;
L
Linus Torvalds 已提交
2183 2184
}

2185 2186
core_initcall(sock_init);	/* early initcall */

L
Linus Torvalds 已提交
2187 2188 2189 2190 2191 2192
#ifdef CONFIG_PROC_FS
void socket_seq_show(struct seq_file *seq)
{
	int cpu;
	int counter = 0;

2193
	for_each_possible_cpu(cpu)
2194
	    counter += per_cpu(sockets_in_use, cpu);
L
Linus Torvalds 已提交
2195 2196 2197 2198 2199 2200 2201

	/* It can be negative, by the way. 8) */
	if (counter < 0)
		counter = 0;

	seq_printf(seq, "sockets: used %d\n", counter);
}
2202
#endif				/* CONFIG_PROC_FS */
L
Linus Torvalds 已提交
2203

2204 2205
#ifdef CONFIG_COMPAT
static long compat_sock_ioctl(struct file *file, unsigned cmd,
2206
			      unsigned long arg)
2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217
{
	struct socket *sock = file->private_data;
	int ret = -ENOIOCTLCMD;

	if (sock->ops->compat_ioctl)
		ret = sock->ops->compat_ioctl(sock, cmd, arg);

	return ret;
}
#endif

2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240
int kernel_bind(struct socket *sock, struct sockaddr *addr, int addrlen)
{
	return sock->ops->bind(sock, addr, addrlen);
}

int kernel_listen(struct socket *sock, int backlog)
{
	return sock->ops->listen(sock, backlog);
}

int kernel_accept(struct socket *sock, struct socket **newsock, int flags)
{
	struct sock *sk = sock->sk;
	int err;

	err = sock_create_lite(sk->sk_family, sk->sk_type, sk->sk_protocol,
			       newsock);
	if (err < 0)
		goto done;

	err = sock->ops->accept(sock, *newsock, flags);
	if (err < 0) {
		sock_release(*newsock);
2241
		*newsock = NULL;
2242 2243 2244 2245 2246 2247 2248 2249 2250 2251
		goto done;
	}

	(*newsock)->ops = sock->ops;

done:
	return err;
}

int kernel_connect(struct socket *sock, struct sockaddr *addr, int addrlen,
2252
		   int flags)
2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284 2285 2286 2287 2288 2289 2290 2291 2292 2293 2294 2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306 2307 2308 2309 2310 2311 2312 2313 2314 2315 2316 2317 2318 2319 2320 2321
{
	return sock->ops->connect(sock, addr, addrlen, flags);
}

int kernel_getsockname(struct socket *sock, struct sockaddr *addr,
			 int *addrlen)
{
	return sock->ops->getname(sock, addr, addrlen, 0);
}

int kernel_getpeername(struct socket *sock, struct sockaddr *addr,
			 int *addrlen)
{
	return sock->ops->getname(sock, addr, addrlen, 1);
}

int kernel_getsockopt(struct socket *sock, int level, int optname,
			char *optval, int *optlen)
{
	mm_segment_t oldfs = get_fs();
	int err;

	set_fs(KERNEL_DS);
	if (level == SOL_SOCKET)
		err = sock_getsockopt(sock, level, optname, optval, optlen);
	else
		err = sock->ops->getsockopt(sock, level, optname, optval,
					    optlen);
	set_fs(oldfs);
	return err;
}

int kernel_setsockopt(struct socket *sock, int level, int optname,
			char *optval, int optlen)
{
	mm_segment_t oldfs = get_fs();
	int err;

	set_fs(KERNEL_DS);
	if (level == SOL_SOCKET)
		err = sock_setsockopt(sock, level, optname, optval, optlen);
	else
		err = sock->ops->setsockopt(sock, level, optname, optval,
					    optlen);
	set_fs(oldfs);
	return err;
}

int kernel_sendpage(struct socket *sock, struct page *page, int offset,
		    size_t size, int flags)
{
	if (sock->ops->sendpage)
		return sock->ops->sendpage(sock, page, offset, size, flags);

	return sock_no_sendpage(sock, page, offset, size, flags);
}

int kernel_sock_ioctl(struct socket *sock, int cmd, unsigned long arg)
{
	mm_segment_t oldfs = get_fs();
	int err;

	set_fs(KERNEL_DS);
	err = sock->ops->ioctl(sock, cmd, arg);
	set_fs(oldfs);

	return err;
}

2322 2323 2324 2325 2326
int kernel_sock_shutdown(struct socket *sock, enum sock_shutdown_cmd how)
{
	return sock->ops->shutdown(sock, how);
}

L
Linus Torvalds 已提交
2327 2328 2329 2330 2331 2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342
/* ABI emulation layers need these two */
EXPORT_SYMBOL(move_addr_to_kernel);
EXPORT_SYMBOL(move_addr_to_user);
EXPORT_SYMBOL(sock_create);
EXPORT_SYMBOL(sock_create_kern);
EXPORT_SYMBOL(sock_create_lite);
EXPORT_SYMBOL(sock_map_fd);
EXPORT_SYMBOL(sock_recvmsg);
EXPORT_SYMBOL(sock_register);
EXPORT_SYMBOL(sock_release);
EXPORT_SYMBOL(sock_sendmsg);
EXPORT_SYMBOL(sock_unregister);
EXPORT_SYMBOL(sock_wake_async);
EXPORT_SYMBOL(sockfd_lookup);
EXPORT_SYMBOL(kernel_sendmsg);
EXPORT_SYMBOL(kernel_recvmsg);
2343 2344 2345 2346 2347 2348 2349 2350 2351 2352
EXPORT_SYMBOL(kernel_bind);
EXPORT_SYMBOL(kernel_listen);
EXPORT_SYMBOL(kernel_accept);
EXPORT_SYMBOL(kernel_connect);
EXPORT_SYMBOL(kernel_getsockname);
EXPORT_SYMBOL(kernel_getpeername);
EXPORT_SYMBOL(kernel_getsockopt);
EXPORT_SYMBOL(kernel_setsockopt);
EXPORT_SYMBOL(kernel_sendpage);
EXPORT_SYMBOL(kernel_sock_ioctl);
2353
EXPORT_SYMBOL(kernel_sock_shutdown);